Currently, I am using a Sandisk class 2 microsd card with my nookcolor. I know that people have recommended Class 4 or 6, but really, I haven't had any complaints with significant lags etc. I was on Amazon today and saw that they had a Sandisk 16 gig class 2 card for about 14 bucks. I'm tempted to copy my card over to it and of course increase the partition size. Are there any opinions on this? The price sure seems right...